Catalytic and adsorbent gel



Patented Dec. 25, 1928.

UNITED. STATES PATENT OFFICE.

WALTER A. PATRICK, BALTIMORE, MARYLAND, ASSIGNOR TO THE SILICA GEL CORPORATION, 0]! BALTIMORE, MARYLAND,

A CORPORATION OF MARYLAND.

CATALYTIC AND ADSOBBINT GEL.

No Drawing. Original application fled February 88, 1920, Serial No. "888,138. Divided and this applioation flled larch 15, 1828. lerial'llo. 84,860.

The present invention, which is a division of my application Serial No. 362,138 filed February 28, 1920, relates to adsorbent gels having chemically active or catalytic agentsassociated therewith, and more particularly to such gels having a nickel bearing material associated therewith. f

In my Patent No. 1,297 724 I have disclosed the method of making a hard, highl porous silica gel, stable up to 700 C. an

ultra-microscopic pores.

It is the principal object of the present invention to produce els similar in physical structure to the gel described in the above patent, but which possess special properties due to the incorporationof a nickel bearing material, for example, nickel oxide.

The present invention comprehends a hard, stable, porous material having ultra-microscopic res substantially the same as the silica ge mentioned above, and having associated therewith a nickel bearing material.

From a chemical standpoint, it is very desirable to have certain substances in a physical structure similar to that of a porous gel such as the silica gel described in said patent. Silica is an inert substance chemically, and for this reason is admirably suited for adsorbing and removing gases andvapors, provided, of course, that it has the proper porous structure. On the other hand, other substances, such as nickel and nickel oxide, are known to possess desirable chemical and catalytic properties. If this metal or metallic oxide can be obtained with a structure similar to that of the gel described in the patent, the above properties are enhanced and made more active, because of the large surface presented. According to the present invention it is possible to obtain a gel of the structure disclosed in the patent having a nickel bearing material, such as nickel or nickel oxide, incorporated therewith.

In the preparation of silica gel as described in the patent, use is made of the reaction between a soluble silicate and an acid to produce colloidal silicic acid. It is found necessary to allow the silicic acid to set to a hydrogel in a medium of certain definite acid concentration, .in order to insure a gel of the proper structure. The'concentration of the acid in the mixture is from about three tenths t nineteu h g am ns of.-hyd rogen perhaving cally,

analogous to silica gel.

litre, the preferred concentration being about five tenths gram ions of h drogen per litre.

If a mixture of nickel c loride, water glass and hydrochloric acid be repared of such a nature that the. whole will set to a hydrogel, 1t 1s found that it is ossible to entirely free the mixture of 'ChlOIldG by washing without loss of much nickel. the washing depends upon the amount of acid used in the original mixture.

I f improper proportions are taken, a pre-. cip-itate Wlll result and the product of the present invention not be obtained. On the other hand, if the proper proportions and quantities. are taken, the mixture adually hardens into a hydrogel, The hydiogel by washing and drying is converted into the highly porous gel of the present invention. The precipitate mentioned above, after being washed and dried,ma be the same, chemias the gel, but it oes not have the same porous structure. The gel has much finer The loss of nickel inpores than the dried precipitate, and consequently the internal surface of, the gelis many t1mes as extensive as the internal surface of the dried precipitate. It is because of this extensive surface that the gel of the present invention is so active catalytically.

- In reparing the gels, the liquid after mixing s ould have an acid concentration of three tenths to nine tenths gramions of hydro en per litre. The product obtained after was ing and drying is a hard lassy material having a porous structure su stantially' the same as silica gel and consistin of a colloidal oxide, and nickel oxide or "kel.

It is easily possible to reduce a mixture of the silica and obtain a mixture of silica and finely divided nickel, the whole possessing a structure The nickel oxide may be reduced to finely divided nickel with hydrogen at a low temperature.

according to the present invention it is possible to obtain hard, adsorbent gels including I nickel or nickel oxide, this mixture bein secured from a nickel salt, a silicate and aci the proportions and. concentrations being such as to give an acid concentration of three tenths to nine tenths gram ions of hydroen per litre, in the liquid obtained by mixmg solutions of the ingredients,

The term silica gel as used in the specification and claims, designates a hard, p0- rous material having a porous structure similar to that of the silica gel obtained by the process described in Patent N 0. 1,297 ,7 24.

The term nickel bearing material as used in the specification and claims is intended to designate the metal nickel by itself as well as compounds thereof.

vHaving thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. A hard stable material having a orous structure substantially the same as sihca gel 15 and consisting ofa colloidal oxide and nickel.

2. A hard stable non-precipitated silica gel having ultra-microscopic pores and havmg nickel associated therewith.

3. A hard stable material having a porous structure substantially the same as silica gel and consisting of a colloidal oxide and a nickel bearing material.

4. A hard stable non-precipitated silica gel having ultra-microscopic pores and havlng a nickel bearing material associated therewith.

In testimony whereof I hereunto afiix my I signature.

WALTER A. PATRICK. 

